1. Field of the Invention
The present invention relates to a knob attached to an upper end of a shift lever of a manual transmission.
2. Description of the Prior Art
A known shift lever knob consists of a surface layer made of soft vinyl chloride, an insert made of a synthetic resinous material and screwed onto an upper end of a shift lever and a filling made of soft vinyl chloride and disposed between the surface layer and the insert. This shift lever knob is light in weight, e.g., weighs about 100 g since it is entirely made of a synthetic resinous material, resulting in the problem that the shift lever vibrates efficiently in response to vibrations of the transmission.
Another known shift lever knob consists of a surface layer made of soft vinyl chloride and an insert-and-filling made of cast iron. This shift lever knob is too heavy since it is entirely made of cast iron except for the surface layer, resulting in the problem that the transmission is liable to slip out of gear and the structural strength of the shift lever is liable to be undesirably low. Another problem is that there is a difficulty of locating the knob so that the shift pattern faces the front of the vehicle since the core and the shift lever are engaged at their threaded portions made of metal.